Starbucks' across America are running out of a key ingredient

Starbucks' pink drink became an Instagram sensation, driving customer demand for coconut milk.Starbucks InstagramStarbucks across the country are running out of coconut milk, thanks to the runaway success of two new beverages.

The chain debuted the limited-time offering to highlight its coconut milk, which the company launched in 2015. Customers had already been utilizing the non-dairy option this summer to create "secret menu" beverages, such as the hugely-popular pink drink.

Now, it seems that coconut milk may have become a little too popular at the coffee chain.

"Are you out of coconut milk, too?" Reddit user barista 1738 asked in the Starbucks subreddit on Tuesday. "We have been out of coconut milk for the past few days and people are pissssed."

Looking at social media reveals that the barista is far from alone.

Starbucks' Twitter has been flooded with complaints of locations lacking in coconut milk.

The problem seems to be impacting locations across the US.

Some customers are reporting that their local Starbucks locations have been coconut milk-free for days.

"Starbucks why is there no coconut milk in upper Manhattan?" reads one such comment. "I went to 3 stores they all said none until at least the weekend."

Starbucks did not respond to Business Insiders' request for comment.

On one hand, it's good news for Starbucks that customers are responding positively to new beverages made with coconut milk, both in the form of iced coconut milk mocha macchiato and the pink drink, which is made with strawberry açaí refresher and coconut milk.

Starbucks' iced coconut milk mocha macchiato is a coconut milk-based is a take on Starbucks' iced caramel macchiato.Starbucks

"Coconut milk is one of those things that our customers were asking for," Starbucks' coffee education specialist Mackenzie Karr told Business Insider prior to the launch of the iced coconut milk mocha macchiato. "When we launched last year it was hugely successful. So, the next step seemed — let's build a beverage around it."

However, when customer demand exceeds supply, it can create some serious problems for the company.

In May, Starbucks told Business Insider that locations were expected to increase their coconut milk orders prior to the launch of the iced coconut milk mocha macchiato. Clearly, some locations underestimated exactly how many customers would be jumping on the coconut milk bandwagon this summer, and are now coming up short — and, in the process, enraging customers attempting to try a new, limited-time offering or flaunt a pink drink on Instagram.